Opabiniidae
| Opabiniidae Temporal range: Middle Cambrian - Middle Ordovician, | |
|---|---|
| Opabinia (top) and Utaurora (bottom) | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Stem group: | †Dinocaridida |
| Family: | †Opabiniidae Walcott, 1912 |
| Genera | |
Opabiniidae is an extinct family of marine stem-arthropods. Its type and best-known genus is Opabinia. It also contains Utaurora, and Mieridduryn. Opabiniids closely resemble radiodonts, but their frontal appendages were basally fused into a proboscis. Opabiniids also distinguishable from radiodonts by setal blades covering at least part of the body flaps and serrated caudal rami.